232 research outputs found
ICP-MS and MALDI-TOF: an integrated approach in the study of metal-protein interactions in biological samples
No full textThe activity and stability of most of proteins in a biological organism are subject
to metal ion binding. Heavy metals such as arsenic and mercury are able to interact with proteins and, due to their impact on human health and environmental pollution, they represent a priority investigation field. Moreover, the contribution of these metals to the pathological processes, requires an in-depth understanding of the
protein targets. Studying the nature of these interactions require the most appropriate analytical method. In order to verify the most suitable operational conditions, the in vitro interactions in proteins-rich foodstuffs (such as: milk, eggs and food grade gelatin) with some As and Hg compounds have been evaluated. Then, some naturally exposed samples have been analyzed in order to study any in vivo interactions. Samples have been separated using SEC chromatography and metals eluted
have been detected by ICP-MS, while proteins have been identified by MALDI-TOF. The results showed that arsenical compounds had strictly species-specific interactions,
while for mercury compounds fewer differences have been found. Since the
use of ICP-MS for the analysis of biomolecules containing heteroatoms can give us several advantages in terms of sensitivity and specificity, a part of this PhD thesis has been devoted to protein labeling techniques. The study has been focussed on the development of an HPLC-ICP-MS hetero-atom tagging method for the identification of intact proteins isolated from painting layers. The proteins labeling has been performed using the metal element-chelated tag (MECT) procedure. The analytical procedure has been firstly tested on proteins standard. Then, the characterization of proteinaceous binders typically used in paints from past centuries has been performed. The proteins extraction and purification procedures have been evaluated using reconstructed pictorial models before testing the effectiveness of the method on some unknown samples.Arsenico e mercurio metalli noti perla loro capacità di interagire con le proteine e, a causa dell’ impatto che hanno sulla salute e sull’inquinamento ambientale, essi rappresentano un campo d’indagine prioritario. Data la natura dell’interazione
metallo-proteina, è stata valutata la metodica più adatta per lo studio di questo
tipo di interazioni. Le condizioni operative sono state inizialmente sviluppate in vitro utilizzando alimenti ricchi di proteine quali: latte, uova e colla di pesce in presenza di alcune specie di As e Hg. Successivamente, alcuni campioni naturalmente
contaminati sono stati analizzati con lo scopo di individuare in vivo le interazioni
che questi metalli hanno instaurato con la componente proteica. Gli analiti sono stati separati con colonna SEC. L’eluizione dei metalli è stata rilevata tramite ICPMS,
mentre le proteine sono state identificate con strumentazione MALDI-TOF. I risultati ottenuti mostrano che la reattività chimica dell’arsenico è strettamente specie-specifica, mentre per le specie mercurio minori differenze sono state trovate. Poiché l’uso della strumentazione ICP-MS per lo studio delle biomolecole contenenti eteroatomi ha offerto innegabili vantaggi in termini di sensibilità e specificità, nella seconda parte della tesi di dottorato è stato valutato l’utilizzo delle tecniche
di marcatura delle proteine con metalli. Lo studio si è focalizzato nello sviluppo di
una metodica HPLC-ICP-MS per l’identificazione delle proteine estratte da strati pittorici. La derivatizzazione delle proteine è stata effettuata utilizzando la tecnica del metal element-chelated tag (MECT). La procedura analitica è stata sviluppata utilizzando inizialmente delle proteine standard. Successivamente è stata eseguita la caratterizzazione delle proteine presenti nei leganti pittorici tipicamente utilizzati negli affreschi e sono state valutate le procedure di estrazione più appropiate utilizzando dei modelli pittorici ricostruiti in laboratorio. Infine, per testare l’efficacia del metodo sviluppato, alcuni campioni incogniti di strati pittorici sono stati analizzati
Educazione e spazio. Proposte di rigenerazione tra pedagogia e architettura
No full textThis essay proposes an interdisciplinary dialogue between pedagogy and architecture, starting from the terms "form" and "formation". The concept of innovation is then taken up in two areas of possible synergy between pedagogy and architecture: the spaces of school education and urban regeneration environments
Methods for the genetic manipulation of marine bacteria
No full textGenetic manipulation of bacteria is a procedure necessary to obtain new strains that express peculiar and defined genetic determinants or to introduce genetic variants responsible for phenotypic modifications. This procedure can be applied to explore the biotechnological potential associated with environmental bacteria and to utilize the functional properties of specific genes when inserted into an appropriate host. In the past years, marine bacteria have received increasing attention because they represent a fascinating reservoir of genetic and functional diversity that can be utilized to fuel the bioeconomy sector. However, there is an urgent need for an in-depth investigation and improvement of the genetic manipulation tools applicable to marine strains because of the paucity of knowledge regarding this. This review aims to describe the genetic manipulation methods hitherto used in marine bacteria, thus highlighting the limiting factors of the different techniques available today to increase manipulation efficiency. In particular, we focus on methods of natural and artificial transformations (especially electroporation) and conjugation because they have been successfully applied to several marine strains. Finally, we emphasize that, to avoid failure, future work should be carried out to establish tailored methodologies for marine bacteria.How to cite: Zeaiter Z, Mapelli F, Crotti E, et al. Methods for the genetic manipulation of marine bacteria. Electron J Biotechnol 2018;33. https://doi.org/10.1016/j.ejbt.2018.03.003. Keywords: Conjugation, Electroporation, Genetic manipulation, Genome engineering, Marine bacteria, Metagenomic library, Natural competence, Next-generation DNA sequencing, Single-cell genome analysis, Suicide vectors, Transformatio
Impact of DC Transient Disturbances on Harmonic Performance of Voltage Transformers for AC Railway Applications
No full text: This paper analyzes the impact of typical DC transient events occurring in railway grids on the frequency performance of instrument transformers (ITs) installed onboard trains and in AC substations for power quality (PQ) applications. PQ monitoring in railway systems is an issue of great interest because it plays a key role in the improvement of energy efficiency. The measurement chain for the PQ measurements, at 15 kV at 16.7 Hz and 25 kV at 50/60 Hz, commonly includes ITs to scale the voltage to levels fitting the input of the measurement units. Nevertheless, the behavior of ITs in the presence of PQ phenomena represents an open issue from a normative point of view, even for those installed in conventional AC power supply systems. In this context, the paper presents a possible definition of DC transient disturbances test waveforms, a measurement procedure, and a setup to assess the impact of these disturbances on the harmonic performances of ITs for railway systems. Preliminary experimental tests carried out on two commercial ITs under wide ranges of variation for the amplitude and the time duration of DC disturbances show that, in some cases, the error introduced in harmonic measurements can exceed 100%
Woolf at the Scriblerus Club, or, Orlando Meets the Augustans
No full textIn Orlando (1928), Virginia Woolf defines a potential path towards the renewal of biography, a path that, while moving away from tradition, maintains a strong bond with eighteenth-century culture. The paper considers how Woolf’s engagement with this particular past articulates her modern point of view on life writing. I am most interested in those aspects of eighteenth-century culture that work subversively against the hierarchical and androcentric aspects of the Victorian biographical tradition. In particular, looking back at James Boswell’s The Life of Samuel Johnson (1791), Woolf seems to encourage a form of ‘copartnership’ between Orlando’s biographer and his/her elusive subject aimed at preserving human complexity and hybridity in biographical portrayals; moreover, the experimentalism of the Augustan female rake and Woolf’s awareness of some early attempts at female self-representation inform her understanding of the place of women, as biographers and as subjects, within the English biographical tradition
Mounier educatore: quel mistero chiamato persona
No full textThis article focuses on the philosophy of personalism and its educational applications, especially the author develops a pedagogical analysis on the Mounier’s personalist idea. According to Mounier, we must respect “the inviolable mystery of the person” because the person is the highest value
Mounier educatore: quel "mistero" chiamato persona
No full textThis article focuses on the philosophy of personalism and its educational applications, especially the author develops a pedagogical analysis on the Mounier’s personalist idea. According to Mounier, we must respect “the inviolable mystery of the person” because the person is the highest value
Medium chain fatty acids in intrauterine growth restricted and small for gestational age pregnancies
No full textNanovectors Design for Theranostic Applications in Colorectal Cancer
No full textColorectal cancer (CRC) is a diffused disease with limited therapeutic options, none of which are often curative. Based on the molecular markers and targets expressed by the affected tissues, numerous novel approaches have been developed to study and treat this disease. In particular, the field of nanotechnology offers an astonishingly wide array of innovative nanovectors with high versatility and adaptability for both diagnosis and therapy (the so called “theranostic platforms”). However, such complexity can make the selection of a specific nanocarrier model to study a perplexing endeavour for the biomedical scientist or clinician not familiar with this field of inquiry. This review offers a comprehensive overview of this wide body of knowledge, in order to outline the essential requirements for the clinical viability evaluation of a nanovector model in CRC. In particular, the differences among the foremost designs, their specific advantages, and technological caveats will be treated, never forgetting the ultimate endpoint for these systems development: the clinical practice
Dataset for the pubblication "Impact of DC Transient Disturbances on Harmonic Performance of Voltage Transformers for AC Railway Applications"
No full textThis is the dataset for the paper published:
Letizia, P.S.; Signorino, D.; Crotti, G. Impact of DC Transient Disturbances on Harmonic Performance of Voltage Transformers for AC Railway Applications. Sensors 2022, 22, 2270. https://doi.org/10.3390/s22062270This project 19NRM05 IT4PQ has received funding from the EMPIR programme co-financed by the Participating States and from the European Union's Horizon 2020 research and innovation programme. Funder name: European Metrology Programme for Innovation and Research (EMPIR) Funder ID: 10.13039/10001413
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